Nearly a year ago I wrote that in crude terms the Islamic State’s (ISIS’s) “military strength comes from the remnants of Saddam Hussein’s military-intelligence apparatus and the Caucasus’ Salafi-jihadists.” Since then I have dug up some answers for why this is so that did not seem to be widely shared. This might be about to change.

Yesterday, the Associated Press reported that the ex-military and -intelligence personnel of the Saddam regime within ISIS are “a major reason for the group’s victories in overrunning large parts of Iraq and Syria.”

AP went on to record the “common trajectory” of men like Major Taha Taher al-Ani, a member of Saddam’s military, who, during the invasion of Iraq, packed up the weapons on his base and joined at-Tawhid wal-Jihad, the group led by Abu Musab az-Zarqawi that would become al-Qaeda in Mesopotamia (AQM) and ultimately ISIS.

A couple of weeks ago I noted that the best-known ex-Saddamists in ISIS had “joined ISIS in 2003 when it was a foreign-led organization with Zarqawi—the patron saint of the takfiriyeen (those who regard only Salafi-purists as Muslims)—as its emir. A ‘socialist infidel’—as ISIS refers to Baathists—was not going to pass muster in ISIS at that time.”

The reason ex-Saddamists could pass muster as sincere Salafists as early as 2003 was because the fabled secularism of the Saddam regime had given way, beginning no later than 1989, and the Islamization of the regime seriously intensified after 1993 when Saddam began al-hamla al-imaniya (The Faith Campaign), intending to create a Ba’ath-Salafist fusion that would provide the regime some legitimacy

One of the most striking things about the AP report is its mention of the Faith Campaign, which media reports about Iraq thus far generally have not. AP added that Saddam’s regime “tolerate[d] religious piety or even radical views among military personnel,” even if it distrusted them. “Most of the army and intelligence officers serving with IS are those who showed clear signs of religious militancy during Saddam days,” an intelligence source told AP. “The Faith Campaign … encouraged them.”

Because “most of the officers who were sent to the mosques [both to infiltrate the institutions and for religious instruction] were not deeply committed to Baathism by that point, … many became more loyal to Salafism than Saddam,” [former intelligence officer Joel] Rayburn notes. Some graduates of the Faith Campaign left the Ba’athist component behind altogether and adopted a “pure” Salafism, which put them on a collision course with the regime …

Still, the long-standing “purist” Salafi opponents of the regime were empowered alongside the Ba’athist-Salafists … and Saddam’s regime gave Iraq “an extra push in the direction of an authentic Islamization process,” as [scholar of Iraqi Islam, Amatzia] Baram puts it.

It is for this reason that it is more accurate to refer to former regime elements (FREs) rather than “Ba’athists” in describing the personnel of the Saddamist military-intelligence apparatus who still operate in the Iraqi insurgency and ISIS: … The most prominent FREs within ISIS … have been there since 2003-04, and had given up Ba’athism for a variant of Salafism long before that.

The Islamization of Saddam’s regime has been a particularly difficult point to get across. One reason is a remnant of the argument over the Iraq invasion: it is very important to the opponents of the invasion—who include more than a few of those who decide what’s fit to print—that Saddam’s regime be presented as implacably hostile to militant Islam so that the regime’s long connection with al-Qaeda can be denied, and George W. Bush can be indicted for creating a problem where none existed. The idea that the regime was evolving along lines that might have produced something like ISIS no matter what we did—mixing together Saddamism and al-Qaeda-style religious militancy by tapping into the global jihadist networks—has to be excluded from the frame of possibilities.

Another reason Saddam’s Islamization program gets left out of accounts is the argument over what Saddam himself actually believed. I would argue that the evidence is that Saddam saw his mosque-building and the imposition of the Holy Law as penance before god. Saddam pressed on with the alliance with Islamists abroad and Islamization internally over the objections of very senior officials, including Tariq Aziz, part of the Quartet that kept Saddam in power, and his intelligence chief and half-brother Barzan Ibrahim. But it should also be understood that it does not actually matter what Saddam believed: his government instituted a “shari’a-lite” regime; it would be cold comfort to the prostitutes beheaded in public squares by Saddam’s Fedayeen that Saddam didn’t really think execution was appropriate. Saddam also strengthened the Salafist trend and made imams and religious teachers into community leaders—policies that would cast a long shadow after the regime was gone.

AP named Abu Muslim al-Turkmani (real name: Fadel al-Hiyali), a major in Saddam’s army and (at least until he was allegedly killed in November) ISIS’s overall deputy and the man who oversaw all operations in Iraq, as a salient individual example of the Saddamist-to-ISIS transition, and also mentioned the Fedayeen Saddam as an important institutional example of this transition, points I made in April.

Haji Bakr (Samir Abd Muhammad al-Khlifawi), a former colonel in Saddam’s army who masterminded ISIS’s expansion into Syria, and Abu Abdulrahman al-Bilawi (Adnan Ismail Najem al-Bilawi), the former captain in Saddam’s army who, until his death in June 2014, led ISIS’s Military Council, believed to be the most important ISIS military institution, also get a mention from AP, as they did from me several weeks ago.

“After al-Zarqawi’s death in a 2006 U.S. airstrike, his Iraqi successor, Abu Omar al-Baghdadi, began to bring in more Iraqis … That process was accelerated when Abu Bakr al-Baghdadi took over … in … 2010,” AP notes. Or, as I put it in early July, “ISIS had been moving toward Iraqization since at least 2006…; this process would be completed in 2010-11.”

The FREs within ISIS were ignored for far too long by the press, and then they were misinterpreted as showing that ISIS was not an Islamist phenomenon but a resurgent Ba’athism wrapping itself in a shahada for tactical reasons. It now seems we are making progress.